CFL k's question...

powerslide

Well-Known Member
how can you tell how many K's a cfl bulb has without it saying on the box? i bought a 42w ge bulb and researched online and found it was 2700k, it omits a orange color. my other 3 26w cfls are a bluish color but i dont have the box to do the research to find out how many k's they are... can anyone tell me how many k's they are? or point me in the right direction. im thinking the color might be a give away but not sure.

from what ive read i want 2700k for germ/veg is this correct?
 

robbzilla

Well-Known Member
Look on the ballast part of the bulb. It should have wattage, volts and K all in one little group.
 

Crazygrowguy99

Active Member
Most bulbs don't have the kelvin on the bulb.

We'll anyways you can normally tell by the color, a bluish white color is 6500k which is good for vegging. A reddish more daylight color, is 2700k which is for flowering it's not like really red or anything but you can definately tell the difference.

If you tell me the serial number I will tell you what K it is.
 

robbzilla

Well-Known Member
Well most of the ones I buy have them right on the ballast. Really you can just tell by the color.
 

makinthemagic

Well-Known Member
how can you tell how many K's a cfl bulb has without it saying on the box? i bought a 42w ge bulb and researched online and found it was 2700k, it omits a orange color. my other 3 26w cfls are a bluish color but i dont have the box to do the research to find out how many k's they are... can anyone tell me how many k's they are? or point me in the right direction. im thinking the color might be a give away but not sure.

from what ive read i want 2700k for germ/veg is this correct?
those yellow bulbs are 2700k, the blue ones are probably 5600k. i think you have the same ones i do. the color is a dead giveaway. the # of k's a bulb has describes its color, lower being more red, higher being more blue. 2700k's are best for flowering, but since they put out so many more lumens than those 5600k's they are also useful in veg.
 

Cransi

Well-Known Member
2700k's are best for flowering, but since they put out so many more lumens than those 5600k's they are also useful in veg.
Well my vegg cfl's are 6500K an they are the same lumen(1600) as my 2700K bulbs, maybe the specific 5600k bulbs are lower in lumen. If that is the case then why even bother with the 5600K bulbs an just get the 6500K bulbs to keep the lumen constant?
 

robbzilla

Well-Known Member
Well my vegg cfl's are 6500K an they are the same lumen(1600) as my 2700K bulbs, maybe the specific 5600k bulbs are lower in lumen. If that is the case then why even bother with the 5600K bulbs an just get the 6500K bulbs to keep the lumen constant?
Exactly....your not really supposed to use 5000K bulbs.....and I don't think I've ever seen a 5600K bulb. Only if you get up to the higher wattages, like 150w-200w, you would have to use a 5000k because really they dont make 6500k that high of wattage. Well they do but its hard to find even on the internet.
 

powerslide

Well-Known Member
so where can you get 6500k in a 42w bulb i went to lowes and walmart and neither have the right k's in the 42w bulbs
 

Cransi

Well-Known Member
so where can you get 6500k in a 42w bulb i went to lowes and walmart and neither have the right k's in the 42w bulbs
Good luck finding them their. I have yet to see a 42w 6500k CFL by the major companies(G.E./Sylvania) at WW, HD, or Lowes. There are websites that offer them like Express Light Bulbs, I just googled "42watt 6500k CFL" there where quite a few to choose from.
 
Top